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<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Revision Numbers Are Different Now</title><link rel="stylesheet" href="styles.css" type="text/css" /><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /><link rel="start" href="index.html" title="Version Control with Subversion" /><link rel="up" href="svn.forcvs.html" title="Appendix B. Subversion for CVS Users" /><link rel="prev" href="svn.forcvs.html" title="Appendix B. Subversion for CVS Users" /><link rel="next" href="svn.forcvs.directories.html" title="Directory Versions" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Revision Numbers Are Different Now</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="svn.forcvs.html">Prev</a> </td><th width="60%" align="center">Appendix B. Subversion for CVS Users</th><td width="20%" align="right"> <a accesskey="n" href="svn.forcvs.directories.html">Next</a></td></tr></table><hr /></div><div class="sect1" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="svn.forcvs.revnums"></a>Revision Numbers Are Different Now</h2></div></div></div><p>In CVS, revision numbers are per-file. This is because CVS
stores its data in RCS files; each file has a corresponding RCS
file in the repository, and the repository is roughly laid out
according to the structure of your project tree.</p><p>In Subversion, the repository looks like a single
filesystem. Each commit results in an entirely new filesystem
tree; in essence, the repository is an array of trees. Each of
these trees is labeled with a single revision number. When
someone talks about “<span class="quote">revision 54</span>”, they're talking
about a particular tree (and indirectly, the way the filesystem
looked after the 54th commit).</p><p>Technically, it's not valid to talk about “<span class="quote">revision 5
of <code class="filename">foo.c</code></span>”. Instead, one would say
“<span class="quote"><code class="filename">foo.c</code> as it appears in revision
5</span>”. Also, be careful when making assumptions about the
evolution of a file. In CVS, revisions 5 and 6 of
<code class="filename">foo.c</code> are always different. In Subversion,
it's most likely that <code class="filename">foo.c</code> did
<span class="emphasis"><em>not</em></span> change between revisions 5 and
6.</p><p>Similarly, in CVS a tag or branch is an annotation on the
file, or on the version information for that individual file,
whereas in Subversion a tag or branch is a copy of an entire
tree (by convention, into the <code class="filename">/branches</code>
or <code class="filename">/tags</code> directories that appear at the top
level of the repository, beside <code class="filename">/trunk</code>). In
the repository as a whole, many versions of each file may be
visible: the latest version on each branch, every tagged
version, and of course the latest version on the trunk
itself. So, to refine the terms even further, one would often
say “<span class="quote"><code class="filename">foo.c</code> as it appears in
<code class="filename">/branches/REL1</code> in revision
5.</span>”</p><p>For more details on this topic, see <a class="xref" href="svn.basic.in-action.html#svn.basic.in-action.revs" title="Revisions">the section called “Revisions”</a>.</p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="svn.forcvs.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="svn.forcvs.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="svn.forcvs.directories.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Appendix B. Subversion for CVS Users </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Directory Versions</td></tr></table></div></body></html>
